This feature was available and working in version 4.12, but is now broken in version 5.1.1.
Trying to import a gcode file results in an error: "Failed to import the selected printer profiles".
An fff file can be imported, but a gcode file cannot.
The V5 gcode files actually include much more information now about the settings used for the print. For example, if you setup a dual extrusion print and look at the gcode files in V4 and V5, you will see that V5 now includes the separate settings for each process, giving you everything you need to recreate that print. V4 wasn't able to include settings for more than a single process, so it didn't work well for many types of prints.
There isn't an option to import the settings from the gcode in V5, but it at least has a full list of each option for each process. You can use that to verify any settings changes that might have been made.